Gymnastic Machine for Weightlifting

ABSTRACT

A gymnastic machine for weightlifting includes: a load-bearing frame, two opposite first lateral guides, upward-downward, developed according to a first direction, two first slides each slidingly constrained on a corresponding first lateral guide, two opposite second lateral guides, developed according to a second direction transversal to the first direction, and each defined on board of one of the first slides, two second slides each slidingly constrained on a corresponding second lateral guide, a lifting bar, each of the ends of the lifting bar being constrained to a corresponding second slide, a motorised transmission configured for applying to the first slides either an opposing force to an upward thrust force, or a downward traction force.

BACKGROUND OF THE INVENTION 1. The Field of the Invention

The invention relates to a gymnastic machine for weightlifting.

2. The Relevant Technology

Nowadays, in weightlifting, bodybuilding and fitness gyms in general, strength and hypertrophy training is carried out mainly using a barbell, i.e., a grip bar, normally made of steel, provided with load bodies at the opposite ends.

Today, the free barbell is the main equipment for athletic training and preparation in the weight room; the athlete applies the desired load to the ends of the barbell, secures it, using locking devices, and begins the performance of a predetermined exercise.

When using particularly high loads, the athlete needs external help from one or more wingmen, who must be immediately available in order to complete the exercise safely, since there are no safety devices that can intervene in the event of an injury to the athlete when he is lifting the barbell.

One of the main limitations of the training with barbells described above is therefore related to the fact that such a training cannot be carried out in total safety if not in the presence of particularly attentive wingmen prepared to intervene to support the athlete in any moment of need.

Another limitation of known type barbell training is the numerous downtimes required to replace or add new and/or different load bodies at the opposite ends of the grip bar.

A further limitation of barbell training is the fact that the physical performance of the athlete is not detectable with continuity and precision since the available parameters are only the weight of the barbell and the time of execution of the exercise.

SUMMARY OF THE INVENTION

The task of the present invention is to develop a gymnastic machine for weightlifting capable of obviating the aforementioned drawbacks and limitations of the known art.

In particular, one object of the invention is to develop a gymnastic machine that is safe and can be used by an athlete without any auxiliary wingmen being present when needed.

Another object of the invention is to develop a gymnastic machine that will allow eliminating the downtimes of replacing, removing or adding loads, which are typical actions of using the barbells known today.

Still, one object of the invention is to develop a gymnastic machine capable of continuously and accurately detecting the athlete's performance.

The above mentioned task and objects are achieved by a gymnastic machine for weightlifting according to claim 1.

Further characteristics of the gymnastic machine according to claim 1 are described in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The aforesaid task and objects, together with the advantages that will be mentioned hereinafter, are indicated by the description of an embodiment of the invention, which is given by way of non-limiting example with reference to the attached drawings, where:

FIG. 1 represents a perspective view of a gymnastic machine according to the invention;

FIG. 2 represents another perspective view of the gymnastic machine of FIG. 1;

FIG. 3 represents a sectional side view of the gymnastic machine according to the invention;

FIG. 4 represents a side view of the gymnastic machine according to the invention;

FIG. 5 represents a sectional view of a detail of the gymnastic machine according to the invention;

FIG. 6 represents a top view of the detail shown in FIG. 5;

FIG. 7 represents a sectional view of another detail of the gymnastic machine according to the invention;

FIG. 8 represents a front view of the detail of FIG. 7;

FIG. 9 represents an operating diagram of the gymnastic machine according to the invention;

FIG. 10 represents a schematic view of a variant embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the above-mentioned figures, a gymnastic machine for weightlifting according to the invention is shown as a whole with the number 10.

Said gymnastic machine 10 comprises:

-   -   a load-bearing frame 11,     -   two opposite first lateral guides 12 and 13, upward-downward,         developed according to a first direction X1,     -   two first slides 14 and 15 each slidingly constrained on a         corresponding first lateral guide 12 and 13,     -   two opposite second lateral guides 16 and 17, developed         according to a second direction X2 transversal to the first         direction X1, and each defined on board of one of the first         slides 14 and 15,     -   two second slides 18 and 19 each slidingly constrained on a         corresponding second lateral guide 16 and 17,     -   a lifting bar 20, each of the ends 20 a, 20 b of said lifting         bar 20 being constrained to a corresponding second slide 18 and         19,     -   motorised transmission means 21 configured to apply to the first         slides 14 and 15 either an opposing force to an upward thrust         force, or a downward traction force.

In the embodiment of the invention described herein by way of a non-limiting example of the invention itself, the load-bearing frame 11 comprises a ground support base 40, such as a quadrangular frame, within which a user is positioned.

Two opposite shoulders 41 and 42 supporting the first lateral guides 12 and 13 develop from the ground support base 40.

In the present example embodiment, each of the shoulders 41 and 42 comprises two uprights 43 and 44 and an upper crosspiece 45.

In the present example embodiment, the first direction X1 is substantially vertical, i.e., unless unavoidable construction and installation tolerances.

The two opposite first lateral guides 12 and 13 each comprise two bars 46 and 47 respectively, which develop between the base 40 and an overlying crosspiece 45.

The first lateral guides 12 and 13 are each located within the arc defined by the uprights 43 and 44 and the crosspiece 45.

The two first slides 14 and 15, as clearly shown in the side view of FIG. 4 and the section of FIG. 5, each comprise:

-   -   two first slider sleeves 48 and 49,     -   at least one transverse element, for example two transverse         elements 50 and 51, rigidly connecting the two slider sleeves 48         and 49.

The first slider sleeves 48 and 49 slide on the respective bars 46 and 47 of the first lateral guides 12 and 13 by interposition of one or more friction reducing devices 52 and 53, for example one or more linear recirculating ball bearings, highlighted in FIG. 5.

In the present example embodiment, the second lateral guides 16 and 17 each comprise a guide bar 54, clearly visible in FIGS. 3, 4 and 5, fixed by brackets 55 between the sleeves 48 and 49 of the respective first slide 14 and 15 to which they belong.

The guide bar 54 is also positioned between the two transverse elements 50 and 51 of the first slide 14 and 15.

The two second slides 18 and 19 each comprise, as clearly shown for the second slide 18 in FIGS. 7 and 8, a second slider sleeve 58 to which a collar 59 is fixed, configured for the constraint with an end 20 a or 20 b of the lifting bar 20.

The collar 59 develops according to a direction orthogonal to the direction of development, and translation, of the second slider sleeve 58.

The second slider sleeve 58 slides on the respective guide bar 54 of the corresponding second lateral guide 16 and 17 by interposition of one or more friction reducing devices 60 and 61, for example one or more linear recirculating ball bearings, highlighted in FIG. 7.

The lifting bar 20 is constrained at the ends 20 a and 20 b to a corresponding collar 59 of a second slide 18 and 19 by friction reducing devices, for example rolling bearings 62.

Such friction reducing devices are configured to allow the ends 20 a and 20 b of the lifting bar 20 to rotate by an angle of less than 10° about the axis X2 of the guide bar 54; this possibility to rotate, although modest, allows the athlete to perform his exercises even in a slightly asymmetrical manner.

The motorised transmission means 21 comprise, in the present example embodiment, two electric motors 22 and 23.

Each of the two electric motors 22 and 23 is configured to actuate a corresponding longitudinally developed flexible element 24 and 25.

In a variant, not illustrated for simplicity but intended to be included in the present invention, the gymnastic machine according to the invention comprises a single electric motor configured to actuate both longitudinally developed flexible elements.

Such longitudinally developed flexible elements 24 and 25 may comprise a belt, a chain, a rope or other similar and equivalent elements.

In the present example embodiment, the longitudinally developed flexible elements 24 and 25 each comprise a toothed belt.

The motorised transmission means 21 comprise, for each longitudinally developed flexible element 24 and 25, as schematised in the section of FIG. 3:

-   -   at least one lower pulley, for example a lower pulley 26,         configured and positioned to deflect a longitudinally developed         flexible element 24 and 25 coming from an electric motor 22 and         23 towards a lower portion 14 a and 15 a of a said first slide         14 and 15,     -   at least one upper pulley, for example two respective upper         pulleys 28 and 29; said upper pulleys are configured and         positioned to deflect a corresponding longitudinally developed         flexible element 24 and 25 towards an upper portion 14 b and 15         b of a first slide 14 and 15,     -   a drive pulley 27, fixed to the corresponding electric motor         shaft 22 and 23.

Each of the longitudinally developed flexible elements 24 and 25, or, henceforth, the belts 24 and 25 for convenience of exposition, defines a circuit that develops starting from a lower part 14 a and 15 a of a first slide 14 and 15, turns around the lower pulley 26, the drive pulley 27, the upper pulleys 28 and 29, up to the upper portion 14 b and 15 b of the same first slide.

Thus, each electric motor 22 and 23, with the corresponding longitudinally developed element 24 and 25 and the corresponding first slide 14 and 15, creates a movement circuit of a first slide 14 that is independent of the other movement circuit of the other first slide 15.

The fixing of a belt 24 and 25 to the respective first slide 14 and 15 is made by fixing means to be understood as being of a type known in itself.

Such motorised transmission means 21 therefore comprise two symmetrical assemblies each comprising pulleys 26, 27, 28 and 29 and a toothed belt 24 or 25.

Each assembly is enslaved to a first, vertical slide 14 and 15, and transmits a vertical linear translatory motion to said first slide 14 and 15.

The pulleys act as deflectors that allow the respective belt 24 and 25 to bypass the load-bearing frame 11 and be driven by the electric motor 22 and 23 through the drive pulley 27.

Each longitudinally developed flexible element 24, 25, in this case each belt 24 and 25, has a respective safety counterweight 35.

Such a counterweight 35 is positioned, for example, on an upward-downward section of each belt 24 and 25.

This counterweight 35 is intended to be able to be positioned also in another position.

Said counterweight 35 is configured and positioned so as to nullify, with electric motors 22 and 23 switched off, the weight contribution given by the first slides 14 and 15 and by the second slides 18 and 19.

In this way, with switched off or faulty electric motors 22 and 23, and brakes of the electric motors not in operation, no load is placed on the user athlete and his safety is ensured.

The counterweight 35 is obviously placed on a section 24 a and 25 a of the longitudinally developed flexible element 24 and 25, i.e., of the belt 24 and 25, where the first slide 14 and 15 is not present.

In the present example embodiment, the counterweight 35 is fixed to the belt 24 and 25 in the section 24 a and 25 a between the drive pulley 27 and the first upper pulley 28.

The gymnastic machine 10 comprises an electronic control unit 90, configured to control and manage the operation of said motorised transmission means 21.

Such an electronic control unit 90 is schematically illustrated by a box in FIG. 1.

The electric motors 22 and 23 are preferably, but not exclusively, of the brushless type.

Said electric motors 22 and 23 may be associated with a corresponding torque reducer, to be understood, of course, as a known type in itself. The reducer can be two-stage or three-stage.

In particular, each of the electric motors 22 and 23 comprises an encoder and an integrated brake.

The gymnastic machine 10 may also comprise an additional speed transducer, for each of the first slides 14 and 15.

This additional transducer is capable of directly measuring the speed of the corresponding first slide 14 and 15.

The encoder on board of the electric motor 22 and 23 detects the speed of the first slide 14 and 15 indirectly, based on the rotational speed of the encoder disc itself.

This additional speed transducer is installed on board of the machine and connected to the electronic control unit 90.

The gymnastic machine 10 advantageously also comprises a signalling device 85, schematised in FIGS. 1 and 8, configured to signal the grasping and release of said lifting bar 20 by a user, which signalling device is connected to said electronic control unit 90.

In the present example embodiment of the invention, which is not limiting thereto, such a signalling device 85 comprises a pair, or alternatively two pairs, of elements, an emitter and a receiver, e.g., photocells, located at opposite ends 20 a and 20 b of the lifting bar 20; for example, an emitting photocell is positioned at a first end 20 a and an opposite receiving photocell is positioned at the opposite end 20 b, or vice versa.

The emitter and the receiver are positioned on the lifting bar 20, in a position to detect the presence of a hand on the same lifting bar 20.

In an alternative embodiment of the invention, schematised in FIG. 10, the signalling device 185 comprises at least one pair of elements, an emitter 185 a and a receiver 185 b, positioned facing a grasping area of the lifting bar 20 so as to detect the presence or absence of a single hand of the athlete on the lifting bar 20.

Still in particular, the signalling device 185 comprises two pairs of elements, a first pair of emitter 185 a and receiver 185 b elements and a second pair of emitter 185 c and receiver 185 d elements, each pair of elements being positioned to detect the presence or absence of a corresponding athlete's hand on the lifting bar.

This alternative solution is particularly effective and is insensitive to any bending of the lifting bar 20.

Preferably, and advantageously, the emitter and receiver elements are mounted on the lifting bar 20 with position adjustment means along the same lifting bar 20.

Such means, which are to be understood to be of a known type, may be a band of plastic material, or a metal sleeve with means for clinging to the bar, or other similar and equivalent reversible fixing means.

The possibility of moving the emitter and receiver along the lifting bar 20 makes the signalling device 85 and 185 particularly versatile and easily adaptable to the specific ergonomics of the athlete.

Said signalling device 85 is configured to operate so that the signal, which passes just above the lifting bar, preferably flush with the surface of the lifting bar 20 itself, is interrupted by the athlete's hand being closed.

The signal remains interrupted until the user athlete opens one hand, or both hands.

When the user athlete releases his grip, for whatever reason, when he opens his hands the signal between emitter and receiver becomes active again, signalling the interruption of the use of the gymnastic machine 10.

Preferably, all electronic components are of the safety-integrated type.

The signalling device 85 is also connected to the electronic control unit 90.

The electronic control unit 90 comprises, for example, a PLC.

Said electronic control unit 90 is interconnected to the encoders of the electric motors 22 and 23 and by means of said encoders receives signals such as to be able to calculate position, speed and acceleration of the lifting bar 20.

The electronic control unit 90 comprises a man-machine interface system, for example a panel with a touch screen; via the screen, the user athlete intervenes in the management of the motorised transmission means 21, determining the load for the physical weightlifting exercise.

Through the same screen, the user athlete has the possibility of viewing and extracting the statistics of his training.

The beginning and the end of the execution of one or more exercises are signalled through the hands-on type signalling device 85, whereby the closing of one hand around the lifting bar signals the start of the execution of an exercise, while the opening, whether voluntary or involuntary, of both hands forces the stop of the exercise machine 10.

In particular, therefore, the electronic control unit 90 allows the gymnastic machine 10, through the action of the electric motors 22 and 23, to replicate the action of the force of gravity on the lifting bar 20, whose load is decided and set by the user athlete through the same electronic control unit 90.

The electronic control unit 90 is configured, and therefore programmed, in such a way that, when the gymnastic machine 10 is switched on, the initial state of the lifting bar 20, i.e., its position in particular, is first checked.

Once the user athlete has selected a workload, the lifting bar 20 is positioned, by slow speed movements, at a fixed height above the ground.

The user athlete positions himself inside the frame 11 of the gymnastic machine 10, ready to perform his exercise; the user athlete signals his presence by means of the hands-on signalling device 85 and performs, under a minimum load, two repetitions; in this way, the machine records the maximum and minimum heights that the barbell reaches during the real exercise.

After the execution of the repetitions under minimum load there is the actual execution of the exercise.

Again through the hands-on signalling device 85, the athlete requests the application of the workload, and starts training.

The electronic control unit 90 detects position, speed and acceleration of the lifting bar 20 in real time, so as to perform the following operations:

-   -   recording and analysis of the athlete's performance;     -   detection of possible fatigue of the athlete, to which the         gymnastic machine 10 shall compensate with appropriate and         calibrated load reductions, in order to allow the safe         completion of the exercise;     -   detection of any dangerous situations, e.g., collision between         the lifting bar and the athlete, fall of the lifting bar, loss         of consciousness of the athlete.

The end of the exercise is signalled by the opening of the athlete's hands, otherwise always gripping the lifting bar 20.

The electric motors 22 and 23, by delivering torque, tension the belts 24 and 25 which, in turn, exert a load on the first vertical slides 14 and 15. This is the athlete's training load.

The electric motors 22 and 23, operating according to the signals imposed by the electronic control unit 90, regulate said load so as to:

-   -   reproduce the contributions of inertia, i.e., the increase and         reduction of load that the athlete perceives during the         accelerating and decelerating steps of the movement;     -   adjust the load impressed, i.e., the torque delivered, in the         event of athlete fatigue; this step is optional, chosen by the         athlete, and can be selected via the man-machine interface,         i.e., through the touch screen of the electronic control unit         90;     -   abruptly stop the lifting bar 20 in the event of a danger         signal.

The electronic control unit 90 detects the presence of the athlete through the hands-on signalling device 85, and also detects the position, the speed and the acceleration of each of the electric motors 22 and 23 through their respective on-board encoders.

These signals are recorded and stored by the electronic control unit 90 during the entire execution of the exercise.

The electronic control unit 90 is configured in such a way as to compare, between one repetition and the previous ones, position and speed in order to assess whether the athlete is getting tired, and therefore whether he will be able to complete the exercise independently; if fatigue is detected, the electronic control unit 90 commands the electric motors 22 and 23 to reduce the load.

To ensure the safety of the athlete, the electronic control unit 90 is configured to check at all times:

-   -   the signal of the signalling device 85, and if the signal is         cancelled it means that the athlete has lost the lifting bar 20         or has fainted;     -   the position of the lifting bar 20, so that if it drops below         the bottom dead centre BDC it means that it is crushing the         athlete's body;     -   the speed of the lifting bar 20, so that if it is high near the         bottom dead centre BDC it means that the athlete will not be         able to avoid a collision with the same lifting bar 20;     -   and the downward acceleration of the lifting bar 20, so that if         it goes beyond a certain fraction of g, whereby g is intended to         be the gravitational acceleration, it means that the barbell is         falling free.

A method of operation of the gymnastic machine 10 according to the invention is described below and is schematised in FIG. 9.

This method of operation includes the following operating steps:

-   -   starting the machine, indicated in FIG. 9 with block 100;     -   a preparation step, comprising the following sequence of actions         200:         -   positioning of the barbell, wherein the barbell is brought             to a height set by the athlete; the data of the starting             height is entered by means of the electronic control unit 90             by the user athlete; this positioning is carried out by the             gymnastic machine 10 at low speed; moreover, the athlete             selects the type of exercise and the workload; this step is             schematised by block 101;         -   actuating the hands-on signalling device 85; in this step             the user athlete, ready to perform the exercise, grasps the             lifting bar 20, thus activating the signalling device 85             which signals the presence of a hand on the lifting bar 20,             enabling the user athlete to perform the exercise; this step             is schematised by block 102;         -   performing at least two, preferably three, unloaded             repetitions of the movements of the exercise by the user             athlete, in order to teach, or have the electronic control             unit 90 memorize, the position of the top dead centre TDC             and the bottom dead centre BDC of the stroke of the lifting             bar 20, that is, the points of maximum and minimum ground             clearance that the lifting bar 20 is expected to reach             during the performance of the exercise; this step is             schematised with block 103;         -   reading of the values; the electronic control unit 90             detects the activation of the hands-on signalling device 85,             indicated by the symbol ‘h’, the position x, the speed x′             and the acceleration x″; this step is schematised by the             block 104;         -   analysis of the repetitions and check that the repetitions             performed are regular, that is that the repetitions have             similar BDC and similar TDC; this step is schematised by the             block 105;         -   if the preceding analysis step detects the regularity of the             repetitions, then the user athlete releases the lifting bar             20, allowing the signal to pass in the signalling device 85;             this step of release of the lifting bar 20 is schematised by             the block 107; this control operation is schematised by the             control block 106;         -   if the previous analysis step does not detect the regularity             of the repetitions, then the user athlete performs the             repetitions as per block 103 again; this control operation             is schematised by the control block 106;         -   after release of the lifting bar 20, there is positioning of             the lifting bar 20 itself at the athlete's choice at the top             or bottom dead centre; this step is schematised by the block             108.

With said step 108, the preparation step 200 ends.

The preparation step 200 is followed by the training step 300.

Said training step 300 comprises the following operating steps:

-   -   actuating the hands-on signalling device 85; in this step the         user athlete, ready to perform the exercise, grasps the lifting         bar 20, interrupting the signal between emitter and receiver and         thus activating the signalling device 85, which signals the         presence of a hand on the lifting bar 20, enabling the user         athlete to perform the exercise; this step is schematised by the         block 109;     -   load application, that is, the electric motors 22 and 23 deliver         torque and reach the training load, including inertial         contributions; this step is schematised by the block 110;     -   reading the parameters of position x, speed x′, acceleration x″,         and time t, following activation of the gymnastic machine 10         through the hands-on signalling device 85, i.e. the electronic         control unit 90 detects the interruption of the signal between         the emitter and the receiver of the signalling device 85,         indicated by the symbol h, and also detects the position x,         speed x′ and acceleration x″ of the lifting bar 20, and the time         t of execution of the exercise; this step is schematised by the         block 111;     -   data saving, that is the electronic control unit 90 performs         information storage; this step is schematised by the block 112.

The training step 300 comprises a cycle of safety operations 400 always iterated until the stop step 116 of conclusion of the exercise.

This cycle of safety operations 400 comprises the following operating steps:

-   -   check of the presence of at least one hand of the athlete on the         lifting bar 20 by means of the signalling device 85; this step         is schematised by the control block 113;     -   if the signalling device 85 signals that there are no hands on         the lifting bar 20, then the data saving is carried out,         schematised by the block 114, and the machine is stopped,         schematised by the block 116;     -   if the signalling device 85 signals the presence of hands on the         lifting bar 20, then it is checked whether the height x of the         lifting bar is above or below a threshold value Xs of crushing         the athlete's body; this step is schematised by the control         block 115;     -   if the height x of the lifting bar is below a threshold value Xs         of crushing the athlete's body, then data saving is carried out,         see block 114, and the exercise is stopped, see block 116;     -   if the height x of the lifting bar 20 is above the threshold         value Xs, and therefore the exercise is proceeding within the         predefined safety limits, then it is checked whether the         downward speed x′ of the lifting bar 20 is greater than a         threshold value Xs′; this step is schematised by the control         block 117;     -   if the downward speed x′ is greater than said threshold value         Xs′, then the data saving, see block 114, and the exercise stop,         see block 116, are performed;     -   if the downward speed x′ is less than said threshold value Xs′,         and therefore the exercise is proceeding within the predefined         safety limits, then it is checked if the downward acceleration         x″ of the lifting bar 20 is greater than a threshold value Xs″         of fall of the lifting bar 20; this step is schematised by the         control block 118;     -   if the downward acceleration x″ is greater than said threshold         value Xs″, then data saving, see block 114, and exercise stop,         see block 116, are performed;     -   if the downward acceleration x″ is less than said threshold         value Xs″, then the exercise continues from the load application         step, block 110, or an auxiliary step 500 of possible reduction         of the exercise load intervenes.

Said auxiliary step 500 comprises the following operating steps:

-   -   check of the position x of the lifting bar 20 with respect to         the bottom dead centre position XBDC, schematised by the control         block 119;     -   if the position x is above XBDC, then it is checked if the speed         x′ of the lifting bar 20 falls below a threshold value Xs′ close         to zero before the TDC, schematised by the control block 120;     -   if the position x does not return above XBDC, then it is checked         whether the time t of stay at the BDC is greater than a         threshold value TBDC, i.e., it is checked whether the athlete         succeeds or fails in bringing the load back upwards; this step         is schematised by the control block 121;     -   if the speed x′ of the lifting bar 20 falls below a threshold         value Xs′ close to zero before the TDC, then a load reduction,         schematised by the block 122, intervenes;     -   if the stay time t at the BDC is greater than a threshold value         TBDC, then a load reduction intervenes, see block 122.

When the load is reduced, the training step 300 resumes from the load application step, block 110.

The electronic control unit 90 is therefore configured to reduce the load under predetermined circumstances and to interrupt the exercise, while storing the exercise data in each case.

The reduction of the load can have a limited duration, in fact very often the athlete, after a minimum help, succeeds in resuming independently the execution of the exercise, or it can be permanent, for example, in particular, if the reduction of the load has already occurred several times during the same exercise.

It has in practice been established that the invention achieves the intended task and objects.

In particular, with the invention, a safe gymnastic machine has been developed which can be used by an athlete without the presence of auxiliary wingmen in case of need, since the same motorised transmission means 21, governed by the electronic control unit 90, apply the load to the lifting bar 20 and retain the same in case of injury or fatigue of the athlete.

Furthermore, with the invention a gymnastic machine has been developed which allows to eliminate the downtimes of replacement, removal or addition of loads, actions typical of the use of the barbells known today, being such gymnastic machine devoid of masses to be replaced, added or removed.

In addition, with the invention a gymnastic machine capable of continuously and accurately detecting the athlete's performance has been devised.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept; moreover, all the details may be replaced by other technically equivalent elements.

In practice, any components and materials can be used, as well as any dimensions and contingent shapes, according to requirements and the prior art, as long as they are compatible with the specific use.

If the characteristics and techniques mentioned in any claim are followed by reference signs, these reference signs are to be intended for the sole purpose of increasing the intelligibility of the claims and, consequently, such reference signs have no limiting effect on the interpretation of each element identified by way of example from these reference signs. 

1. A gymnastic machine for weightlifting, comprising: a load-bearing frame, two opposite first lateral guides, upward-downward, developed according to a first direction (X1), two first slides each slidingly constrained on a corresponding first lateral guide, two opposite second lateral guides, developed according to a second direction (X2) transversal to said first direction (X1), and each defined on board of one of said first slides, two second slides each slidingly constrained on a corresponding second lateral guide, a lifting bar, each of the ends of said lifting bar being constrained to a corresponding second slide, motorised transmission means configured to apply on said first slides either an opposing force to an upward thrust force, or a downward traction force, wherein said motorised transmission means comprise two electric motors each of which is configured to actuate a corresponding longitudinally developed flexible element, each longitudinally developed flexible element being connected at a first end to the lower part of a first slide and at a second opposite end to the upper part of the same first slide, said motorized transmission means comprising, for each longitudinally developed flexible element: at least one lower pulley configured and positioned to deflect a longitudinally developed flexible element coming from a said electric motor towards a said lower part of a said first slide, at least one upper pulley configured and positioned to deflect a said longitudinally developed flexible element towards an upper part of a said first slide.
 2. (canceled)
 3. (canceled)
 4. The gymnastic machine according to claim 1, further comprising an additional speed transducer, for each of the first slides.
 5. The gymnastic machine according to claim 1, further comprising an electronic control unit for controlling the operation of said motorised transmission means.
 6. The gymnastic machine according to claim 1, wherein said electric motors are of the brushless type.
 7. The gymnastic machine according to claim 1, wherein each of said electric motors comprises an encoder and an integrated brake.
 8. The gymnastic machine according to claim 1, wherein said longitudinally developed flexible elements comprise a belt, a chain, a rope or other similar and equivalent elements.
 9. The gymnastic machine according to claim 5, further comprising a device for signalling the grasping and release of said lifting bar by a user, said signalling device being connected to said electronic control unit.
 10. The gymnastic machine according to claim 1, wherein each longitudinally developed flexible element has a safety counterweight.
 11. The gymnastic machine according to claim 5, wherein said electronic control unit is configured to check at all times: the signal of said signalling device, the position of said lifting bar, the speed of said lifting bar, and the downward acceleration of said lifting bar.
 12. A method of operation of a gymnastic machine according to claim 5, comprising the following operating steps: starting the machine; a preparation step, comprising the following sequence of actions: positioning of the barbell, wherein the barbell, that is said lifting bar, is brought to a height set by the athlete; actuating the hands-on signalling device, which signals the presence of a hand on the lifting bar, enabling the user athlete to perform the exercise; performing at least two unloaded repetitions of the movements of the exercise by the user athlete, in order to teach, or have the electronic control unit memorize, the position of the top dead centre (TDC) and of the bottom dead centre (BDC) of the stroke of the lifting bar, that is, the maximum and minimum ground clearance points that the lifting bar is expected to reach during the exercise; reading of the values by the electronic control unit, which detects the activation (h) of the hands-on signalling device, the position (x), the speed (x′) and the acceleration (x″) of said lifting bar; analysis of the repetitions and check that the repetitions performed are regular, that is that the repetitions have similar bottom dead centres (BDC) and similar top dead centres (TDC); if the previous analysis step detects regularity of the repetitions, then the user athlete releases the lifting bar, allowing the signal to pass in the signalling device; if the previous analysis step does not detect the regularity of the repetitions, then the user athlete performs the repetitions again; after release of the lifting bar, there is positioning of the lifting bar at the top dead centre (TDC) or bottom dead centre (BDC).
 13. The method according to claim 12, wherein said preparation step is followed by a training step, said training step comprising the following operating steps: actuating the hands-on signalling device; load application, that is, the electric motors deliver torque and reach the training load; reading of the parameters of position (x), speed (x′), acceleration (x″) and time (t), following the activation of the gymnastic machine by means of the hands-on signalling device, said electronic control unit detecting the interruption of the signal between emitter and receiver of the signalling device, and detects the position (x), speed (x′) and acceleration (x″) of said lifting bar and the time (t) of execution of the exercise; data saving, that is, the electronic control unit performs information storage.
 14. The method according to claim 13, wherein said training step comprises a cycle of safety operations always iterated until a stop step of conclusion of the exercise.
 15. The method according to claim 14, wherein said cycle of safety operations comprises the following operating steps: check of the presence of at least one of the athlete's hands on the lifting bar by means of said signalling device; if the signalling device signals that there are no hands on the lifting bar, then data saving is carried out and the machine is stopped; if the signalling device signals the presence of hands on the lifting bar, then it is checked whether the height (x) of the lifting bar is above or below a threshold value (Xs) of crushing the athlete's body; if the height (x) of the lifting bar is below a threshold value (Xs) of crushing the athlete's body, then data saving and exercise stop are performed; if the height (x) of the lifting bar is above the threshold value (Xs), and therefore the exercise is proceeding within the predefined safety limits, then it is checked if the downward speed (x′) of the lifting bar is greater than a threshold value (Xs′); if the downward speed (x′) is greater than said threshold value (Xs′), then data saving and exercise stop are performed; if the downward speed (x′) is less than said threshold value (Xs′), and therefore the exercise is proceeding within the predefined safety limits, then it is checked if the downward acceleration (x″) of the lifting bar is greater than a threshold value (Xs″) of fall of the lifting bar; if the downward acceleration (x″) is greater than said threshold value (Xs″), then data saving and exercise stop are performed; if the downward acceleration (x″) is less than said threshold value (Xs″), then the exercise continues with a load application step, or an auxiliary step of possible reduction of the exercise load intervenes. 